For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
BUILDING CODE. The building code of the city.
CHANNEL. A natural or artificial depression of perceptible extent, with definite bed and banks to confine and conduct flowing water either continuously or periodically.
COMMISSIONER. The Commissioner of Natural Resources.
ENCROACHMENT LINES. The lateral limits of lines drawn along each side and parallel to a stream or another body of water, which delineates the floodways and within which the flood carrying capacity of the stream or other body of water is to be preserved. Their location, if along a stream, should be so that the floodway between them will effectively carry and discharge a flood not less than the regional flood.
EQUAL DEGREE OF ENCROACHMENT. A method of determining the location of encroachment lines so that floodplains lands on both sides of a stream are capable of conveying a proportionate share of flood flows. This is determined by considering the effect of encroachment on the hydraulic efficiency of the flood plain along both sides of a stream for a significant reach.
FLOOD. A temporary rise in stream flow or stage which results in inundation of the areas adjacent to the channel.
FLOOD FREQUENCY. The average frequency, statistically determined, for which it is expected that a specific flood stage of discharge may be equaled or exceeded. By strict definition, these terms are designated EXCEEDENCE FREQUENCY but in practical terms FREQUENCY is used. The frequency of a particular stage or discharge is usually expressed as having a probability of occurring once within a specified number of years. See also RECREANCE INTERVAL.
FLOOD FRINGE. The portion of the flood plain outside of the floodway.
FLOOD PEAK. The highest value of stage or discharge attained during a flood event, thus peak stage or peak discharge.
FLOOD PLAIN. The areas adjoining a watercourse which have been or hereafter may be covered by the regional flood.
FLOOD PLAIN MANAGEMENT. The full range of public policies and actions necessary or incidental to the ensuring of wise use of the floodplains, and shall include, but not be limited to, the collection and dissemination of flood control information, actual acquisition of flood plain lands, construction of flood control measures and enactment and administration of codes, ordinances and statutes regulating flood plain land use.
FLOOD PLAIN REGULATIONS. The full range of codes, ordinances and other regulations relating to the use of land and construction within flood plain limits. The term encompasses zoning regulations, subdivision regulations, lakeshore management, sanitary and building codes.
FLOOD PROFILE. A graph or a longitudinal plot of water surface elevations of a flood event along the reach of a stream or river.
FLOODPROOFING. A combination of structural provisions, changes or adjustments to properties or structures subject to flooding primarily for the reduction or elimination of flood damages to properties, water and sanitary facilities, structures and contents of buildings in flood hazard areas.
FLOOD STAGE. As commonly used by the U.S. Weather Bureau and others, that stage, at a particular river gauge, where overflow of the natural banks of the stream results in significant flood damage in any portion of the reach for which the gauge is a representational index.
FLOODWAY. The channel of the watercourse and those portions of the adjoining floodplains which are reasonably required to carry and discharge the regional flood.
REACH. The hydraulic engineering term used to describe the longitudinal segments of a stream or river influenced by a natural or manmade obstruction. In an urban area, the segment of a stream or river between two consecutive bridge crossings would typically constitute a reach.
RECREANCE INTERVAL. The average interval of time, based on statistical analysis of actual or representative stream flow records, which can be expected to elapse between floods equal to or greater than a specified stage or discharge. The RECREANCE INTERVAL is generally expressed in years. See also FLOOD FREQUENCY.
REGIONAL FLOOD. A flood which is representative of large floods known to have occurred generally in Minnesota and reasonably characteristic of what can be expected to occur on on average frequency in the magnitude of the 100-year recurrence interval.
RURAL AREAS. The portion of the city lying outside of the platted area thereof.
STANDARD PROJECT FLOOD. The flood that may be expected from the most severe combination of meteorological and hydrological conditions that is considered reasonably characteristic of the geographical area in which the drainage basin is located, excluding extremely rare combinations. The floods are intended as practicable expressions of the degree of protection that should be sought in the design of flood control works, the failure of which might be disastrous.
URBAN AREAS. The platted area within the corporate limits of the city.
WATERCOURSE. A channel in which a flow of water occurs either continuously or intermittently in a definite direction. The term applies to either natural or artificially constructed channels.
ZONING REGULATIONS. The city’s zoning regulations.
(Prior Code, § 1101.02)